Structural truss with crimp/clamp method of making same

ABSTRACT

A structural truss ( 3 ) with crimp/clamp ( 18 ) and method of making same wherein the truss ( 3 ) includes disposed U-shaped channel chords ( 2 ) and struts ( 1 ) interconnected to one another at alternately extending apices ( 6 ) wherein successive segments of the struts ( 1 ) have U-shapes and inverted U-shapes at their mid-sections and flat apices ( 6 ) at their respective ends. The ends ( 4 ) of successive segments of the unit lengths of the struts ( 1 ) and the chords ( 2 ) have holes for the insertion of a tapered pin ( 9 ), thus precisely controlling the length of successive trusses. The truss member ( 3 ) also has vertical load-bearing strut sections ( 17 ) at the end of each manufactured length of truss ( 3 ) to support a cantilevered section of chord ( 10 ). The crimp/clamp ( 18 ) is crimped and clamped onto the chords ( 2 ) so as to clamp the struts ( 1 ) to the chords ( 2 ).

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation in part of application Ser. No.10/919,601, filed on Aug. 17, 2004 which claims the benefit of U.S.Provisional Application No. 60/496,067, filed Aug. 18, 2003.

BACKGROUND OF THE INVENTION

This invention relates to trusses, more specifically, an improved openweb structural truss and process of making same.

Conventional structural trusses and methods of making same are difficultin some respects.

First, the truss members of predetermined length, as described in U.S.Pat. No. 3,827,117, comprise oppositely disposed U-shaped channelsbetween which a strut member is positioned, comprising alternatelyextending strut segments having flat end portions which are generallyU-shaped in a cross section at the center and gradually tapering towardthe flat end portions at the end. The strut member is then bent at theflat portions to form alternately extending apices which contact theopposing chord elements. When this is done, however, the opposite apicesbecome substantially different in shape, thereby materially affectingthe quality of their connections to the opposing chords. Thus, thereexists a need for improvement in the quality of those connections.

Second, current production machines for the manufacturing of trusses, asdescribed in U.S. Pat. Nos. 3,827,117 and 3,961,738, teach using presetlengths and quantities of trusses being formed continuously on theproduction machinery as controlled by a computer program. Although thesemachines efficiently manufacture the truss members described in thecited prior art at low cost with a minimum of labor and in a manner toprovide uniformity and utility, these machines do not provide thefollowing capabilities: a) providing a means for precise location forfastening struts and chords, b) providing a means for preciselymeasuring the distance points from apex to apex, and c) providing avertical member for the support of the cantilevered ends of each trusslength.

Finally, the quality of current trusses may be compromised at connectingpoints of strut and chords because of lack of uniformity of the shape ofstrut apices.

The prior art includes the following U.S. patents: Patent No. InventorAssignee Filing Date Issue Date D230,265 Ollman C-O, Inc. Aug. 11, 1971Feb. 05, 1974 3,882,653 Ollman C-O, Inc. Mar. 16, 1973 May 13, 19753,827,117 Ollman C-O, Inc. Apr. 11, 1973 Aug. 06, 1974 3,961,738 OllmanC-O, Inc. Jul. 01, 1974 Jun. 08, 1976 4,030,256 Ollman N/A Nov. 20, 1975Jun. 21, 1977

SUMMARY OF THE INVENTION

The primary object of the present invention is to provide an improvedstructural truss that will provide for improved connections of strutapices to the opposing chords.

A further object of the present invention is to provide an improvedapparatus for making identically shaped strut apices contacting each ofthe opposing truss chords.

An even further object of the present invention is to provide animproved apparatus for making truss members which provides a means forprecisely measuring the distance points from apex to apex.

A further object of the present invention is to provide an improvedapparatus for making truss strut members which provides a load-bearingvertical member for the support of the cantilevered end of each truss.

An even further object of the present invention is to provide animproved structural truss with crimp/clamp method that provides bothhorizontal and lateral strength to the strut/chord connection.

The present invention fulfills the above and other objects by providingtwo improved strut segments where one strut segment is inverted U-shapedand the other is U-shaped. By having segments with both a U-shape andinverted U-shape, those portions of the strut contacting the opposingchords will have identically-shaped flat sections to facilitate thejoining of the strut and the chords.

The present invention further fulfills the above objectives by providinga method for making the U-shaped sections of the advancing strut formalternate U-shape and inverted U-shaped sections of each segment in thestrut unit length. The method invention involves providing unit lengthstandards for both strut and chord by punching identically sized andlocated holes at each segment end of successive unit lengths of strutsand of chords. As the separate elements of strut and chords reach thepoint of joining one to the other, a tapered pin will align the strutand chord by entering a first hole on the chord and then a second holeon the strut to precisely join the elements at a prescribed standardunit length. In addition, terminating strut sections of each truss aretruncated to form vertical load-bearing strut segments for the precedingand succeeding truss cantilevered ends.

The above and other objects, features, and advantages of the presentinvention should become even more readily apparent to those skilled inthe art upon a reading of the following detailed description inconjunction with the drawings wherein there is shown and describedillustrative embodiments of the invention.

BRIEF DESCRIPTION OF DRAWINGS

This invention is described by appended claims in relation to adescription of a preferred embodiment with reference to the followingdrawings which are explained briefly as follows:

FIG. 1 is a side elevational plan view of the present invention;

FIG. 2 is a cross sectional view along the line 2-2 of the embodiment ofFIG. 1;

FIG. 3 is a side view of the improved truss of the present invention asa strut is inserted between the chords;

FIG. 4 is a cross sectional view along the line 4-4 of the embodiment ofFIG. 1;

FIG. 5 is a cross sectional view along the line 5-5 of the embodiment ofFIG. 1;

FIG. 6 is a cutaway side view of the present invention illustrating theoperations performed on a cut strut and cut channel of the presentinvention;

FIG. 7 is a side plan view of the crimp/clamp method of the presentinvention;

FIG. 8 is a cross sectional view along the line 8-8 of the embodiment ofFIG. 7;

FIG. 9 is an upward looking view of the crimp/clamp method of thepresent invention;

FIG. 10 is a side view of a first step of a riveting process of thepresent invention; and

FIG. 11 is a side view of a second step of the riveting process of thepresent invention.

DESCRIPTION OF PREFERRED EMBODIMENT

Listed numerically below with reference to the drawings are terms usedto describe features of this invention. These terms and numbers assignedto them designate the same features throughout this description.

-   1. strut member-   2. u-shaped channel/chord-   3. truss member-   4. flat end portion-   5. intermediate portion-   6. apex-   7. open end-   8. closed end-   9. tapered pin-   10. end of chord-   11. notch-   12. cantilevered end-   13. hollow rivet-   14. middle-   15. first end-   16. second end-   17. end strut member-   18. crimp/clamp-   19. centering hole-   20 a. punch-   20 b. punch

With reference to FIGS. 1 and 2, an improved structural truss of thepresent invention is shown. The improved truss has a plurality of strutmembers 1 having a first end 15, a middle 14 and a second end 16. Thestruts 1 have flat end portions 4 on the first end 15 and the second end16 and are connected by non-flat intermediate portions 5 which areU-shaped or inverse U-shaped. The strut member 1 is bent at the flatportions 4 to form alternately extending apices 6. The apices 6 of thestrut members 1 are connected to the U-shaped channels 2 to form thetruss member 3 at its cantilevered end. The U-shaped chord channels 2have notches 11 punched out in equal distances from one another. Thenotches 11 are adjacent to the end pieces 6 of the truss member 3 andprovide for bending the ends 10 of the chord channels 2 inward around anend strut member 17 to define and provide strength to each truss member3. The strut apex 6 and each end of the chords 2 have centering holes 19to accommodate a tapered pin 9. The tapered pins 9 are used to preciselylocate the end points of each unit length of the truss member 3. Eachtruss member 3 has cantilevered ends 12 to form each truss member 3.Apices 6 of the strut 1 will be secured to each chord 2 by using afastening means, such as hollow rivets 13 located on both sides of thetapered pins 9. A hollow rivet 13 also centers the strut 1 within thechord 2. A strut apex 6 may then be crimped and clamped onto the chord iso as to provide additional structural reinforcement for the improvedstructural truss. The last strut members 17 on each end in a trussmember 3 is bent perpendicularly to the chord 2 and the ends of eachchord 10 are bent at a notch 11 to provide closed ends to the trussmembers 3.

In FIG. 3, truss member 3 is shown with the strut member 1 insertedbetween the chords 2. The U-shaped portions of the struts 1 alternate indifferent directions, an open end 7 and a closed end 8, so that thoseportions of the strut members 1 contacting the chord 2 will be identicalin shape.

With reference to FIGS. 4 and 5, cross sectional views of alternatingstrut members 1 are shown to have inverse U-shaped and U-shapedfeatures, respectively. This feature achieves a higher quality of strutmember 1 to chord 10 connection by creating identically shaped apices 6.

With reference to FIG. 6, the method employed in fabricating the trussmembers of the present invention is described. First, a cut is made onthe strut member 1 along lines A-A. The cut struts 17 are then foldedfrom positions S to positions F. Then, another cut is made along lineB-B through the U-shaped chord 2. Because the strut 1 was alreadyfolded, the cut along B-B will not cut the strut members 1. The U-shapedchannel chords ends 10 are then bent from positions X to positions Y toform the truss member 1.

In FIG. 7, a side plan view of the attachment of strut 1 to chord 2 isshown. As noted above, the apices 6 of the strut 1 may be secured toeach chord 2 by using a fastening means, such as hollow rivets 13,located on both sides of the tapered pin 9. However, the attachmentmethod shown has dimples created by crimping/clamping 18 sides of chord2 inward into the strut 1 apex 6, thus clamping the strut 1 to the chord2.

FIG. 8 shows a cross-sectional view along line 8-8 of the embodiment ofFIG. 7 wherein the attachment is achieved by crimping the chord 2 andclamping the strut apice 6 to the chord 2. Centering holes 19 arelocated in the chord 2 and strut 1 for the acceptance of a tapered pin9.

FIG. 9 shows an upward looking view of the crimp/clamp 18 method of thepresent invention.

FIGS. 10 and 11 show side views of a two-step riveting process which maybe used in conjunction with the present invention. Currently, spotwelding is used to secure trusses 1 to chords 2. However, if the weld isfaulty, much time and money is expended in order to fix the weld,especially if the weld is utilized in a floor joist. The two-stepriveting process, which may be used as an alternative or in conjunctionwith the present inventions, provides a secure, interlocked connectionbetween the trusses 1 and the chords 2.

First, as shown in FIG. 10, a punch 20 a is utilized in a downwarddirection so as to create an indentation on the strut 1 and chord 2.Then, as shown in FIG. 11, a punch 20 b, preferably sized slightlysmaller in diameter than the indentation, is utilized in an upwarddirection so as to pierce the strut 1 and chord 2. Because of the upwarddirection of the punch in the second step, the strut 1 and chord 2become locked together, thereby providing a secure fit.

Although the two-step riveting process may be used without alternativesecuring methods, such as the crimp/clamp 18 method described above, thesecuring methods could be used singularly or in conjunction with oneanother.

The use of the present invention will improve the quality of the strutmember to chord element connection.

It is to be understood that while a certain form of the invention isillustrated, it is not to be limited to the specific form or arrangementof parts herein described and shown. It will be apparent to thoseskilled in the art that various changes may be made without departingfrom the scope of the invention and the invention is not to beconsidered limited to what is shown and described in the specificationand drawings.

1. A structural truss with crimp/clamp comprising: at least two strutmembers having at least two alternately extending struts; said at leasttwo alternately extending struts having a first end, a middle and asecond end; said at least two alternately extending struts having a flatend portion on said first end and a flat end portion on said second end;said flat end portion on said first end is connected to said flat endportion on said second end by at least one first non-flat intermediateportion and at least one second non-flat intermediate portion; said atleast one first non-flat intermediate portion is U-shaped; said at leastone second non-flat intermediate portion is inverse U-shaped; said atleast two flat end portions are fastened to at least two chords; a meansfor securing said at least two chords to said at least one U-shapedintermediate portion and said at least one inverse U-shaped intermediateportion; and said at least two chords are parallel in relation to oneanother.
 2. The structural truss with crimp/clamp of claim 1 wherein:said at least two extending struts are bent at said at least two flatportions to form a pair of alternately extending apices.
 3. Thestructural truss with crimp/clamp of claim 1 wherein: said at least twochords have at least one notch per chord.
 4. The structural truss withcrimp/clamp of claim 2 wherein: said at least one notch per chord isadjacent to said apices.
 5. The structural truss with crimp/clamp ofclaim 4 wherein: said apices have at least one hole.
 6. The structuraltruss with crimp/clamp of claim 1 wherein: said at least two chords haveat least one hole.
 7. The structural truss with crimp/clamp of claim 2wherein: said at least two chords have at least one hole; and saidapices have at least one hole.
 8. The structural truss with crimp/clampof claim 1 wherein: said at least two chords are substantially U-shaped.9. A method for making a structural truss with crimp/clamp comprising atleast two strut members having at least two alternately extendingstruts; said at least two alternately extending struts having a firstend, a middle and a second end; said at least two alternately extendingstruts having a flat end portion on said first end and a flat endportion on said second end; said flat end portion on said first end isconnected to said flat end portion on said second end by at least onefirst non-flat intermediate portion and at least one second non-flatintermediate portion; said at least one first non-flat intermediateportion is U-shaped; said at least one second non-flat intermediateportion is inverse U-shaped; said at least two flat end portions arefastened to at least two chords; a means for securing said at least twochords to said at least one U-shaped intermediate portion and said atleast one inverse U-shaped intermediate portion; and said at least twochords are parallel in relation to one another, said method comprisingthe steps of: a. at least partially cutting one said strut at a distancebetween said middle and said second end; and b. positioning the one saidstrut so it is substantially perpendicular to and positioned between thechords.
 10. The method for making a structural truss with crimp/clamp inclaim 9 further comprising a step after step b of: folding ends of thecut chords so they are substantially perpendicular to and positionedbetween the chords.
 11. The method for making a structural truss withcrimp/clamp in claim 9 further comprising a step after step a of: a.punching a hole at each segment end of successive unit lengths of strutsand chords; b. aligning the struts and chords; and c. inserting a pininto the hole on the chord and the hole on the strut to position thestruts and chords at a prescribed standard unit length.
 12. Thestructural truss with crimp/clamp of claim 1 wherein: said means forsecuring said at least two chords to said at least one U-shapedintermediate portion and said at least one inverse U-shaped intermediateportion is via crimping.
 13. The structural truss with crimp/clamp ofclaim 1 wherein: said means for securing said at least two chords tosaid at least one U-shaped intermediate portion and said at least oneinverse U-shaped intermediate portion is via clamping.
 14. The methodfor making a structural truss with crimp/clamp in claim 9 wherein: saidmeans for securing said at least two chords to said at least oneU-shaped intermediate portion and said at least one inverse U-shapedintermediate portion is via crimping.
 15. The method for making astructural truss with crimp/clamp in claim 9 wherein: said means forsecuring said at least two chords to said at least one U-shapedintermediate portion and said at least one inverse U-shaped intermediateportion is via clamping.
 16. The method for making a structural trusswith crimp/clamp in claim 11 further comprising a step after step c of:said means for securing said at least two chords to said at least oneU-shaped intermediate portion and said at least one inverse U-shapedintermediate portion is via crimping.
 17. The method for making astructural truss with crimp/clamp in claim 11 further comprising a stepafter step c of: said means for securing said at least two chords tosaid at least one U-shaped intermediate portion and said at least oneinverse U-shaped intermediate portion is via clamping.